Corrosion-resistant electromagnetic shielding materials with high conductivity and excellent magnetic properties are urgently needed to resolve the issue of electromagnetic radiation pollution. Herein, the renewable and easily degradable cellulose paper after tannin-assisted silver-nanoparticle deposition was designed as the substrate. An electroless copper-plated paper (ECP) with a high conductivity of 4167 s/cm and a low sheet resistance of 5.17 mΩ/sq was used as a conductive layer. The superhydrophobic magnetic surface with a contact angle of 153.5°and a sliding angle of 3.2°was prepared by spraying a mixture of polydimethylsiloxane and clustered Fe 3 O 4 microspheres synthesized by a one-step hydrothermal method. Fe 3 O 4 microspheres were used to construct the surface micro−nano hierarchical structure and improve the impedance matching, and polydimethylsiloxane was used to provide a low surface energy and facilitate the adhesion of ECP to clustered Fe 3 O 4 microspheres. The synergistic effect of the conductive and magnetic layers resulted in the cellulose paper, showing absorption-dominated electromagnetic shielding characteristics with electromagnetic interference shielding effectiveness >50 dB (absorption: reflection ∼95:5). The study provides a promising method for preparing wave-absorbing-based shielding materials with a wide application.

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In this paper, a capillary coated with poly(glycidyl methacrylate) nanoparticles (PGMA NPs) was prepared and applied to construct a capillary electrophoresis (CE) enantioseparation system with glucosyl-β-cyclodextrin (Glu-β-CD) as a chiral selector. The PGMA NP coating can be easily introduced through a simple ring-opening reaction. Two basic drugs were used as models to evaluate the separation performance of the PGMA coating. Under the optimal conditions selected, the separation of the two enantiomers was obtained.

A new anti-swelling agent was synthesized by polymerizing epichlorohydrin and dimethyl amine polymer. The swelling inhibition properties were investigated over clay and shale. It was found that the clay inhibition of swelling properties was greatly enhanced compared with common inorganic salts. However, to shale, the swelling properties did not inhibited efficiently by using prepared polymers. Furthermore, the influence of cross linking of polyammonium to the swelling ability of prepared polymer has been also carried out by using triethylenetetramine cross linking agent. In the case of shale, the swelling inhibit properties was improved after cross link, while opposite swelling effect was observed over clay.

Controlling the concentration of free radicals in polymerization systems is advantageous for preparing cationic polyacrylamide (CPAM) with high molecular weight and acceptable dissolvability. In this study, a novel ultraviolet (UV)-initiated system characterized with adjustable light intensity and redox-azo complex initiator was used to synthesize a CPAM flocculant named NP. Comparatively, another CPAM flocculant named SP with stable UV light intensity and single initiator was prepared. The chemical structure, morphology, and thermal stability were analyzed through instrumental analysis. Proton nuclear magnetic resonance indicated that NP was successfully prepared, and a small fraction of cationic homopolymer was mixed in the product. Polymerization conditions were optimized, and polymerization mechanism was determined by investigating the effects of various parameters on intrinsic viscosity, conversion, and dissolvability. Results showed that the best performance was obtained at indexes of 0.45 wt‰ redox initiator concentration, 0.2 wt‰ azo initiator concentration, 40.0 wt% of cationic monomer, first- and second-stage light intensities of 8.5 and 13 mW/cm2, respectively, and 3 wt% urea. Sludge conditioning performances of NP and SP were comparatively evaluated, and the mechanism was determined by investigating the sedimentation behavior and floc size distribution. High intrinsic viscosity, porous morphology structure, and the mixed cationic homopolymer of NP resulted in better sludge conditioning performance.